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What hit my home brew two metre Yagi antenna?!

catman

catman

Addicted Member
Banned
G'day all, I woke up this morning and looking out my window my home brew (DIY) Yagi looked a bit bent. It was fine yesterday so something must have hit it overnight and bent the reflector element somewhat!

I guess it must have been a large bird, however it's never happened before! It still works ok but the front/ back ratio is obviously not as good as it was!

I use aluminium 'strip' element material (I call it the 2 m 'strip' yagi) and it looks like I'll have to take it down and 'bash' the reflector element back into shape (hopefully). Regards, Felix (vk4fuq) aka catman.
 

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Depressed antenna syndrome.

I'll keep an ear out for you this weekend during the IARU HF contest - I need VK for DXCC :smoke::thmbsp:
 
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How very odd. I found my TV/FM antenna bent one day in March 2010. Musta been one big-ass bird.
When I ran a 30foot/10m black vinyl covered 14ga wire for shortwave, birds used to fly into it daily.

Tom
 

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We lived at the end of a runway when I was a kid.
We lost our TV antenna, when an old biplane crop duster clipped it.
It missed hitting our chimney by less than 3 feet.

Steve
 
catman said:
G'day all, I woke up this morning and looking out my window my home brew (DIY) Yagi looked a bit bent. It was fine yesterday so something must have hit it overnight and bent the reflector element somewhat!

I guess it must have been a large bird, however it's never happened before! It still works ok but the front/ back ratio is obviously not as good as it was!

I use aluminium 'strip' element material (I call it the 2 m 'strip' yagi) and it looks like I'll have to take it down and 'bash' the reflector element back into shape (hopefully). Regards, Felix (vk4fuq) aka catman.
Click to expand...

I vote bird. Big one, at least 5 kg in weight. What do you have down there in that weight class?
 
WoW! :yikes:

Big Bird himself!!

So, does that work pretty good being in vertical orientation? I have never seen one like that....


Good luck fixing it! :thmbsp:
 
G'day all, yes the yagi is normally vertically polarised for local repeater access and local (vertically polarised) simplex FM work, although it works well picking up the ARISS transmissions on 145.800 MHz from the ISS.

I optimised the yagi at about 146.3 MHz and it is quite usable across the whole band of 144 to 148 Mhz, although the SWR rises to around 1.5 :1 at band edges.

The SWR is about 1.05:1 at 146.000 MHz. BTW I took it down and repaired it this morning. A bit of 'panel bashing' was required! :D Regards, Felix (vk4fuq) aka catman.
 
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G'day mate, no 1.5:1 isn't bad but I'm not sure about errors in my reference SWR meter.

My SWR meter is an Oskerblock designed for 2 metres, but it's probably not quite as accurate as a Bird meter. :D Some Ham friends of mine dislike the use of a gamma match, but I find them fine. Regards, Felix (vk4fuq) aka catman.
 
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Your place was visited during the night by a flying Chupacabra, who landed there, looking for prey... consider yourself lucky to get away with only a bent antenna!

:D


Seriously, it must suck to have to take that thing back down and fix it, after the work it took to make it and get it up there in the first place... but on the bright side, it's cool to think that there is at least one BIG bird out there! :yes:
 
G'day mate, being a VHF yagi it's reasonably small and easy to handle (maybe), and in any case it was a good opportunity (excuse) to take down the mast and do some maintenance (tighten mounting bolts, clean up rust etc etc). Anyway it looks ok now and it's working well.

I've designed a few VHF yagi's over the years, but this little one is my favourite. With only three elements, it's a challenge to obtain the highest forward gain. I estimate about 7 dbd of forward gain with a f/b ratio of at least 25 db. Not too bad, I think. Regards, Felix (vk4fuq) aka catman.
 
How to speak Australian:

Rotor.jpg


Rotor.

hi hi om.
 
G'day mate, yep that's how I do it. In any case that yagi normally stays pointed that way (SE)! Regards, Felix (vk4fuq) aka catman.
 
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Hey it works right? Sorry, It just reminded me of the Fosters Beer commercials that used to play here. So, I wonder what kinda bird landed on or hit it?
 
G'day mate, no worries! With all the stuff I've been through in my life, one tends to care mostly about the practical things and if they work, and less about appearance. Regards, Felix (vk4fuq) aka catman.
 
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